1. Field of the Invention
The present invention concerns a pressure capsule, as well as a spray can which utilizes such a capsule.
2. Discussion of the Related Art
It is known that, up to the present time, the pressure in spray cans is often obtain by equipping the can with propellants which produce negative effects on the environment. Such a propellant is, for example, composed of chlorofluoro hydrocarbons, butane, propane or other such substances.
Indeed, such propellants have negative effects not only on the health but, as is generally known, also on the protective ozone layer surrounding the earth, with all its known and unknown consequences.
Hence there is a general movement to exclude the use of such propellants and to offer sprayers and such similar apparatuses in which the pressure needed for expelling a liquid out of a receptacle is built up on the basis of compressed air produced by manually operating a pump that is part of the spray can or similar apparatus. It is obvious, however, that such manual operation of a sprayer or similar apparatus is not attractive in use and that it practically precludes a uniform vaporization.